Broad Autism Phenotypic Traits and the Relationship to Sexual Orientation and Sexual Behavior

Individuals with higher levels of the broad autism phenotype (BAP) have some symptoms of autism spectrum disorder (ASD). Like individuals with ASD, people with higher-BAP may have fewer sexual experiences and may experience more same-sex attraction. This study measured BAP traits, sexual experiences, and sexual orientation in typically developing (TD) individuals to see if patterns of sexual behavior and sexual orientation in higher-BAP resemble those in ASD. Although BAP characteristics did not predict sexual experiences, one BAP measure significantly predicted sexual orientation, β = 0.22, t = 2.72, p = .007, controlling for demographic variables (R2 change = .04, F = 7.41, p = .007), showing individuals with higher-BAP also reported increased same-sex attraction. This finding supports the hypothesis that individuals with higher-BAP resemble ASD individuals in being more likely than TD individuals to experience same-sex attraction

Potential use of hydroelectric facilities for manipulating the fertility of Lake Mead

Analysis of historical nutrient data for Lake Mead indicates that the fertility of the reservoir has decreased which may be the cause for a corresponding decline in the largemouth bass population. However, it appears that fertility can be manipulated by altering the operation of the dam. The depletion of nutrients in the euphotic zone by phytoplankton and subsequent accumulation in the hypolimnion during summer and fall provide a natural nutrient gradient from which water of varying fertility can be drawn for discharge. This combined with alterations in the depth or seasonal pattern of discharge can possibly be used to enhance fertility and bass production in Lake Mead

Mixing in the equatorial surface layer and thermocline

Twelve days of microstructure measurements at the equator (140°W) in November 1984 showed a surprisingly strong effect of both the daily cycle of solar heating and wind on mixing in the upper ocean. Because of limited variations in atmospheric forcing and currents during the experiment, processes in the daily mixing cycle were similar from day to day. Only the intensity of mixing varied. The lower boundary of the diurnal surface layer separated two distinct mixing regimes, the diurnal surface layer and the thermocline. Within the diurnal surface layer (which extended to 10- to 35-m depth), turbulent kinetic energy dissipation rates ε varied relatively little. Although variations in surface layer depth coincided with the daily change in direction of air-sea surface buoyancy production of turbulent kinetic energy (or simply, the surface buoyancy flux), ε was significantly greater relative to the buoyancy flux than was expected for a simple convective layer. In the thermocline below the diurnal surface layer, ε was highly intermittent; the day-night cycle was stronger, and variability was enhanced by turbulent "bursts" of 2-3 hours duration, which may be related to internal wave breaking events. The turbulent heat flux crossing 20-m depth was almost equal to the surface heat flux less the irradiance penetrating below 20 m. Seventy percent of the surface heat flux was transported vertically to the water below 30 m by turbulent mixing. Only a negligible amount penetrated to the core of the Equatorial Undercurrent. The gradient Richardson number Ri distinguishes between statistically different mixing environments. However, ε cannot be predicted from the value of Ri, since the intensity of mixing depends on the intensity of forcing in a way not specified by the value of Ri alone

The Limnological status of Lake Mead and Lake Mohave under present and future powerplant operations of Hoover Dam

The ever-increasing demand for energy in the southwest has led to a search for additional sources of power generation. Coal-fired powerplants currently provide most of the baseline energy in the southwest, but this must be supplemented with hydroelectric power during periods of peak demand. In order to provide additional peaking power, the U.S. Bureau of Reclamation is considering a number of projects to modify existing hydroelectric facilities, or add new facilities in the Lake Mead Recreation Area. The Hoover Powerplant Modification Feasibility Investigation was authorized by Congress on December 16, 1975 to determine the feasibility of: (i) adding one or more hydroelectric generating units to Hoover Dam, (ii) adding one or more reverse turbine pump-storage units to Hoover Dam, and (iii) upgrading the existing generating units for greater capacity (USDI 1978). In addition, offline pump-storage systems are currently being considered for installation in three locations in Lake Mead and one location in Lake Mohave (USDI 1977). The feasibility of these projects, in part, depends upon the impact to recreational and other beneficial uses of the reservoirs and the river. A primary concern is that these projects could significantly alter the physical, chemical, and biological properties of the reservoirs. Therefore, the U.S. Bureau of Reclamation initiated this study to determine: (i) the current limnological status of Lake Mead and Lake Mohave, (ii) the relationship between the physical, chemical and biological factors in Lake Mead and Lake Mohave, and (iii) the effect of the hydroelectric projects on the future limnological status of Lake Mead and Lake Mohave

A pathway for mitotic chromosome formation

Mitotic chromosomes fold as compact arrays of chromatin loops. To identify the pathway of mitotic chromosome formation, we combined imaging and Hi-C analysis of synchronous DT40 cell cultures with polymer simulations. Here we show that in prophase, the interphase organization is rapidly lost in a condensin-dependent manner, and arrays of consecutive 60-kilobase (kb) loops are formed. During prometaphase, ~80-kb inner loops are nested within ~400-kb outer loops. The loop array acquires a helical arrangement with consecutive loops emanating from a central spiral staircase condensin scaffold. The size of helical turns progressively increases to ~12 megabases during prometaphase. Acute depletion of condensin I or II shows that nested loops form by differential action of the two condensins, whereas condensin II is required for helical winding

A Machine Checked Model of Idempotent MGU Axioms For Lists of Equational Constraints

We present formalized proofs verifying that the first-order unification algorithm defined over lists of satisfiable constraints generates a most general unifier (MGU), which also happens to be idempotent. All of our proofs have been formalized in the Coq theorem prover. Our proofs show that finite maps produced by the unification algorithm provide a model of the axioms characterizing idempotent MGUs of lists of constraints. The axioms that serve as the basis for our verification are derived from a standard set by extending them to lists of constraints. For us, constraints are equalities between terms in the language of simple types. Substitutions are formally modeled as finite maps using the Coq library Coq.FSets.FMapInterface. Coq's method of functional induction is the main proof technique used in proving many of the axioms.Comment: In Proceedings UNIF 2010, arXiv:1012.455

The role of the turbulent stress divergence in the equatorial Pacific zonal momentum balance

From a comprehensive set of upper ocean measurements made during a moderate El Niño in boreal spring 1987, we reassess the role of turbulence in transporting momentum vertically at the equator. An examination of the terms in the vertically integrated zonal momentum equations indicates that on short time scales the zonal pressure gradient is not balanced by the surface wind stress despite an apparent balance of these terms on longer (seasonal) time scales. The vertical redistribution of zonal momentum is complex. The strength of the wind determines both the magnitude and, likely, the mechanisms of momentum transport between the surface and the core of the undercurrent. During low wind conditions in April 1987 the turbulent stress divergence was significantly different in magnitude and vertical structure from that found during strong winds in November 1984. In November 1984 the turbulent stress divergence was much too large above 40 m to balance the residual term in the zonal momentum budget of Bryden and Brady (1985, 1989) and decayed exponentially with depth from the wind stress value at the surface. In April 1987 the turbulent stress divergence was smaller than that required by Bryden and Brady and decayed linearly from the surface wind stress. For a proper comparison with Bryden and Brady’s zonal momentum balance, it is necessary to determine the annual average turbulent stress divergence

Limnological aspects of Lake Mead, Nevada-Arizona

Lake Mead is a deep, subtropical, moderately productive, desert impoundment with a negative heterograde oxygen profile occurring during; the summer stratification. investigations of the Boulder Basin of Lake Mead by the University of Nevada were initiated in November 1971. The primary objective of the study was to determine what effects industrial and sewage effluent from the Las Vegas metropolitan area, discharged into Las Vegas Bay, have had on the water quality and limnological conditions of Boulder Basin. Data from the 1975-76 period are presented in detail, with earlier data included in the summaries and discussions. Measurements of water temperature, dissolved oxygen, conductivity, pH. Alkalinity, nutrient concentrations, phytoplankton numbers, chlorophyll a, primary productivity, zooplankton concentrations, and coliform bacteria were made monthly or biweekly. Success patterns for both phytoplankton and zooplankton are described. Physical factors affecting the distribution arid deposition of enteric bacteria (including those of special public health importance) in Las Vegas Bay are discussed. The distribution of water arid of enteric bacteria of possible fecal origin into Las Vegas Bay from Las Vegas Wash were determined. The unreliability of thoroughly referenced techniques and methods, generally accepted as standard for enteric bacteria, are treated in detail. Water from Las Vegas Wash forms a density current in Las Vegas Bay. The density current is located on the bottom during isothermal conditions and in the metalimnion during summer stratification. The metalimnetic oxygen minimum was examined in some detail and found to be caused by biological respiration. Estimations of zooplankton and phytoplankton respiration indicate that they could account for the majority of the oxygen lost in the metalimnion. Primary production and algal biomass were higher in Las Vegas Bay because of nutrient enrichment from Las Vegas Wash. The inner portion of Las Vegas Bay would be classified as eutrophic and the outer portion of Las Vegas Bay and Boulder Basin as mesotrophic. Nitrogen is likely to be the most limiting nutrient

Fine-scale variability at 140°W in the Equatorial Pacific

In November-December 1984 we carried out an intensive 12-day upper ocean sampling program on the equator at 140°W as part of the Tropic Heat Experiment. From our observations we constructed hourly averaged profiles of temperature, salinity, σ₁, turbulent kinetic energy dissipation rate, and horizontal velocity. These data were used to examine the correspondence between hydrographic and velocity fields and to compare the measured turbulent dissipations with the calculated Richardson numbers. We found that the core of the Equatorial Undercurrent tracked a density surface (σ₁ = 25.25) on times as short as 1 hour. The variability in both hydrographic and velocity fields was greatest at the semidiurnal frequency. The supertidal energy was not significantly different from the Garrett-Munk mid-latitude level once latitudinal scaling was removed from the Garrett-Munk model parameters. Horizontal velocity spectra were found to be contaminated by displacement of the background shear. Turbulent dissipation was dominated by a dirunal cycle, with high values of dissipation occurring at night above the undercurrent core. Shear and buoyancy frequency, calculated over 12-m vertical scales, were observed to track each other above the core and were dominated by a diurnal period above 40 m and by a semidiurnal period below 40 m. When shear and buoyancy frequency were combined to form a Richardson number, neither diurnal nor semidiurnal cycles were present. Above the undercurrent core, the Richardson numbers were uniformly small (0.3 to 0.6)

Expanding Economic Opportunity for More Americans: Bipartisan Policies to Increase Work, Wages, and Skills

Many workers today find themselves lacking the skills and training necessary to thrive in the modern economy. Most low- and middle-income workers have not seen meaningful wage increases in many years. Millions of men and women are missing from the workforce altogether. These challenges stem from profound shifts in the American economy and necessitate a dedicated policy response.Over the course of the past year, the Aspen Economic Strategy Group collected policy ideas to address the barriers to broad-based economic opportunity and identified concrete proposals with bipartisan appeal. These proposals are presented here